Curious - predicting earthquakes
Awesome if it pans out -- from
Technology Review:
Spacecraft Saw ULF Radio Emissions over Haiti before January Quake
Back in 2004, the French space agency CNES launched a small satellite called DEMETER into polar orbit some 700 km above the Earth's surface.
DEMETER's is an unusual mission. Its job is to monitor low frequency radio waves generated by earthquakes.
Today, a group of geoscientists release the data associated with the M 7.0 earthquake that struck Haiti in January. They say that DEMETER saw a clear increase in ultralow frequency radio waves being emitted from the Earth's the crust in that region in the build up to the quake.
The anecdotal evidence of electromagnetic effects associated with earthquakes is legion. Various accounts link earthquakes with mysterious light and heating effects. Then there is the widespread evidence that certain animals can sense impending quake, possibly because of a sensitivity to low frequency electric fields.
But good data is hard to come by. Geoscientists have been measuring the currents that flow through Earth beneath our feet for over 100 years. These so-called telluric currents are thought to be generated by friction and piezoelectric effects within rock. And the flow of electrons they cause has been linked to various atmospheric phenomena such as thunderstorms.
But the role these currents play in earthquake physics is unknown. It makes sense that any currents generated by friction and piezoelectric effects should be dramatically influenced by the relative movement of different parts of the crust.
But these effects occur over vast distances and at frequencies that are hard to measure and difficult to separate from background noise. Which is why DEMETER was launched , (DEMETER stands for Detection of Electro-Magnetic Emissions Transmitted from Earthquake Regions).
Very cool!
Posted by DaveH at December 17, 2010 12:14 PM